Re: Postpone evaluation of argument

Righard van Roy <pluijzer@xxxxxxxxx> writes:
I want to add an item to a list, except if the evaluation of that item
results in an exception.

This may be overkill and probably slow, but perhaps most in the spirit
that you're asking.

from itertools import chain

def r(x):
if x > 3:
raise(ValueError)
return x

def maybe(func):
try:
yield func()
except:
return

def p(i): return maybe(lambda: r(i))

your_list = list(chain(p(1), p(5)))
print your_list
.

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